Enforce SavePersistentPrefs in RestartJob path.
Enforce SavePersistentPrefs in RestartJob path.

Settings saved via ScheduleSavePersistentPrefs may be lost if exitted via chromeos::RestartJob.
Evidence of those losses were observed on debug build:
change language on new user pod and then start new incognito session: in ~20-30% cases changed language is lost.

BUG=chromium-os:13102
TEST=Manual

Review URL: http://codereview.chromium.org/6710001

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@78683 0039d316-1c4b-4281-b951-d872f2087c98

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